Rename source file before suggesting in save picker

The source file is now renamed to its filename without extension
before being set as the suggested save file, ensuring consistent
naming in the file picker dialog.

Author: TheJoeFin

Simple Icon File Maker/Simple Icon File Maker/Helpers/FilePickerHelper.cs

@@ -17,6 +17,8 @@ public static async Task TrySetSuggestedFolderFromSourceImage(FileSavePicker sav
             if (File.Exists(imagePath))
             {
                 StorageFile sourceFile = await StorageFile.GetFileFromPathAsync(imagePath);
+                string name = Path.GetFileNameWithoutExtension(imagePath);
+                await sourceFile.RenameAsync(name);
                 savePicker.SuggestedSaveFile = sourceFile;
             }
         }